Ignore Null Value Fields From Rest API Response Java - java

In my project when i send Rest Response to Advance Rest Client It only shows Fields which Have some values and Ignores(Does not show) fields which have NULL Values or Empty values.
Part Of Code:
Gson gson=new Gson();
// firstResponse is Object which contains the values
String jsonString = gson.toJson(firstResponse);
test.saveJson(jsonString); //OR System.out.println(jsonString);
return Response.ok(firstResponse).build(); // Response to Rest Client
Response sample To return Response.ok(firstResponse).build();
Advance rest client From web project :
{
"Name": "smith",
"Properties": {
"propertyList": [
{
"ID": "072",
"Number": "415151",
"Address": "Somewhere"
},
{
"ID": "151",
"Number": "a800cc79-99d1-42f1-aeb4-808087b12c9b",
"Address": "ninink"
},
{
"ID": "269",
},
],
},
}
Now when i save this as Json String in DB or When i want to Print this to console it also prints the fiels with null or empty values:
{
"Name": "smith",
"Properties": {
"propertyList": [
{
"ID": "072",
"Number": "415151",
"Address": "Somewhere"
},
{
"ID": "151",
"Number": "a800cc79-99d1-42f1-aeb4-808087b12c9b",
"Address": "ninink"
},
{
"ID": "269",
"Number": "",
"Address": ""
},
],
},
"resultList" :[]
}
How can i print or save this JSON string same as response in rest client i.e. i dont want to print null or empty value field i just want to ignore them.

in top og entity class , try with the annotation
#JsonInclude(Include.NON_EMPTY)
this annotation don't show any empty field in your json.

Not giving you a code but here are some pointers for you:
Read the manual: How to handle NULL values
You may need to use a custom exclusion strategy
Also read this Q&A: Gson: How to exclude specific fields from Serialization without annotations

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response JSON:
[
{
"persone": {
"name": "To John",
"age": 15
},
"group": "ipsum"
},
{
"persone": {
"name": "To John",
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{
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}
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in the above example, the age attribute is null, and the group attribute is missing in the last object of the list.
My question is how do you create an appropriate class model in that case handling the null and the missing attribute?

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I have a Json object like this in my Postgres DB:
{
"emails": [
{
"email": {
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I want to get the value at the field first inside name.
How i can access in this field using HashMap in java
{ "payload":{
"name": {
"first": "jean",
"last": "bob,
},
"address": {
"code": "75",
"city": "paris",
"country": "France"
},
}}
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Checking Keys in JSON Records using Java

"transaction": {
"id": 1,
"empid": "12345",
"details1": {
"name": "xyz",
"age": "30",
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I need to test if JSON record contains more then two keys(details, Address).
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Given I have the following json structure:
{
"Role": {
"id": "5",
"name": "bb1",
"description": "desc1",
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{
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{
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{
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{
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For example
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